And I have an external PHP file/script to email the results of the form to me. All works fine but I can't figure out how to grab the total dollar amount ("sub_total") that is calculated by the Javascript and returned to a div tag on my form with this line:
document.getElementById('sub_total').innerHTML = '$ ' + runningTotal.toFixed(2);

Is there a way to have the Javascript send this variable to a hidden field on my form which I can then pass to my php script to email? I am able to get the total into a div tag, but not a hidden field.